On Oct. 16, Crowley will moderate the second presidential debate, in Hempstead, N.Y. Unlike the other debates, it will be a town hall-style discussion, with questions coming primarily from "undecided voters" selected by the Gallup polling organization.

On Oct. 22, Bob Schieffer of CBS News will host the final presidential debate, in Boca Raton, Fla. It will focus on foreign policy.

Lehrer has moderated 10 presidential debates, more than any other journalist, and one vice presidential debate. Schieffer has moderated two previous presidential debates. This will be the first time moderating a presidential or vice presidential debate for Crowley and Raddatz.

Three teenage girls from a Montclair, N.J., high school — Emma Axelrod, Elena Tsemberis and Sammi Siegel — had petitioned the commission to include a woman among the presidential debate moderators.

"Women were being overlooked, and while it might not have been an active prejudice, it was definitely there," Axelrod told NPR's All Things Considered on Monday. "So, the fact that now we're closing that gap of 20 years, that is what I'm excited that a woman will bring, the equal representation."